EP1800550A1 - Screening of tobacco material - Google Patents

Abstract

A tobacco particle separator comprises an elongated trough with parallel concave traps, each located under an air jet (14) emerging from an overhead rhomboid plug separated by a gap (25) from the adjacent plug (1). The plugs sub-divide the trough into upper and lower chambers. An independent claim is included for tobacco particle grading, in which air jets are directed at the parallel concave traps. Light particles are raised by the flow of air (15) to the upper chamber for removal and leave heavier particles (13) in the traps.

Description

The invention relates to a viewing device for separating heavy and light particles of tobacco material in a viewing space with at least one classifier nozzle for generating a classifier stream. The invention further relates to a method for separating heavy and light particles of tobacco material in a viewing space, wherein the viewing space has a bottom, wherein tobacco material is introduced into the viewing space and by means of a Sichterstroms which is directed upward, light particles in the upper region of the viewing space be kept, with heavy particles remain in the area of the soil or get there.

A generic sighting device is for example from the EP 0 361 815 E1 known. The disclosed device for separating heavy and light particles of tobacco material comprises means for fluidizing and moving the material to cause heavy particles of acceptable material and comprising a support surface adapted to receive material at a receiving end and means for vibrating the support surface to move the material longitudinally toward a delivery end, the support surface having a pleated and permeable surface which in number is formed by longitudinally extending troughs which are separated by peaks. There are also disclosed airflow means for generating an upward airflow in the troughs. In addition, at least part of the wall of each trough is perforated. The perforations, the shape of the troughs, and the air flow means are arranged to cause the velocity of the upward fluidizing air flow to increase from the bottom of the troughs to the apexes of the convolutions, with openings provided in the troughs are through which the heavy particles can be removed. Thus, there is disclosed a fluidized bed sifting device in which a fluid layer forms in the upper region of the troughs, whereas heavier parts can sink to the bottom of the device and escape from openings in the bottom.

It is an object of the present invention to provide an alternative viewing device and method for separating heavy and light particles of tobacco material.

This object is achieved by a sighting device for separating heavy and light particles of tobacco material in a viewing space, wherein the viewing device comprises at least one classifier nozzle for generating a classifier stream, wherein the classifier nozzle comprises a body which is arranged in the viewing space.

By providing a Sichterdüsenkörpers in the viewing space can very efficiently and effectively the airflow used for sifting can be adjusted. The amount of air needed to create a fluidized bed can also be reduced. In particular, the entire body of the classifier nozzle is arranged in the viewing area. In the context of the invention, the term body also includes the term displacement body.

Preferably, the viewing device is a fluidized bed sifting device. In particular, it is possible by means of the sighting device to produce an upwardly directed, fluidizing air flow which, especially in the upper region of the body of the classifier nozzle, prevails.

The viewing device is particularly efficient when an opening of the classifier nozzle is arranged to the bottom of the viewing device. This means, in particular, that the opening of the classifier nozzle is arranged downwards, ie towards the bottom of the viewing device. Preferably, the opening of the classifier nozzle is arranged in the lower area or in the area which is closest to the ground. The opening or the classifier nozzle is in particular configured in such a way that an air flow from the classifier nozzle is directed onto the floor in bouncing or towards the floor. The bottom is preferably a vibrating conveyor. Preferably, an air jet emerging from the opening of the classifier nozzle exits substantially vertically downwards. It can also be provided exit directions, which extend obliquely downwards. Further, an air flow from the Sichterdüse emerge, which is expanded, and preferably in an angular range of <90 °, in particular preferably <20 °.

A particularly good removal of heavy parts or heavier particles is then present when the bottom of the viewing device is configured with at least one groove. Preferably, a channel is provided for each classifier nozzle or body of a classifier nozzle. When the classifier nozzle is a slit nozzle extending at least partially from a material input to a material dispenser, a particularly efficient separation of heavy and light parts is made possible. The nozzle slot preferably extends substantially over the entire classifier nozzle length.

A particularly good separation and especially particularly good vortex formation of lightweight parts is given when a material input is provided, which is arranged above or in the upper region of the body of the classifier nozzle. Preferably, a material dispensing is provided, which is arranged in the upper region of the body of the classifier nozzle. This material output then serves to output conductive parts or light particles. Heavy particles are preferably discharged through one or more arranged holes, in particular in the bottom, which are arranged in particular below the material output for the light particles.

Preferably, the body of the classifier nozzle is formed in cross-section transversely to a conveying direction of the sighted tobacco material downwardly and upwardly tapering. By this preferred embodiment, on the one hand, an efficient air flow can be generated and on the other hand, a fluidized bed region, which is relatively narrowly limited in terms of vertical expansion.

Preferably, at least two classifier nozzles are provided. If the distance of the classifier nozzles to the bottom is adjustable, the classifying device can be adapted very efficiently to other types of tobacco or other conditions of the tobacco material.

The object is further achieved by a method for separating dissolved heavy and light particles of tobacco material in a viewing space, wherein the viewing space is bounded by a bottom, wherein tobacco material is introduced into the viewing space and by means of a classifier stream, which is directed upward, light particles are held in the upper region of the viewing space, wherein heavy particles remain in the region of the soil or get there, with the classifier stream from a reflection of an air flow, which is directed against the ground results. By this measure, a method is provided which can be carried out for a long time, without the floor, which is provided in conventional Sichtervorrichtungen with holes or perforations to let air out of these streams, must be cleaned. It is very difficult by the method according to the invention to cause contamination or sealing of the classifier nozzle.

Preferably, the air flow is designed such that results in a fluidized bed of light particles in the upper region of the viewing space. The formation of a fluidized bed in this case depends on the flow velocity and the air flow rate of the air flow and in particular on the geometry of the viewing space or arranged in the viewing space body.

Preferably, the tobacco material is introduced in an upper area in the viewing space. Preferably, the soil is shaken. The bottom is preferably a vibrating conveyor. By shaking is meant in the context of the invention, a swing. Preferably, the viewing device or the essential elements of the viewing device, which are provided for sifting and transporting the tobacco materials, from the tobacco inlet or from the material input to the material output sloping or inclined downwards or oriented in the conveying direction or oriented.

For sifting heavy parts of tobacco, in particular rib parts of cut tobacco, a plurality of slot nozzles are arranged above the gutter bottom of a Wirbelschichtsichters, each generating an air jet, which is directed against the channel bottom. From there the air jet is deflected upwards and flows between the slot nozzles. The material to be sighted is placed above the slot nozzles, so that heavy parts fall against the air flow on the channel bottom and the sighted material remains above the slot nozzles.

Fig. 1

eine schematische dreidimensionale Ansicht einer erfindungsgemäßen Sichtvorrichtung,

Fig. 2

eine schematische Schnittdarstellung durch die erfindungsgemäße Sichtvorrichtung aus Fig. 1,

Fig.3

eine schematische dreidimensionale Darstellung der erfindungsgemäßen Sichtvorrichtung aus Fig. 1 von schräg unten,

Fig. 4

eine schematische dreidimensionale Einzelansicht einer Schlitzdüse,

Fig. 5

eine schematische Schnittdarstellung durch die Schlitzdüse aus Fig. 4.

The invention will be described below without limiting the general inventive idea by means of embodiments with reference to the drawings. With respect to all details of the invention not explained in detail, reference is expressly made to the drawings. Show it:

Fig. 1

a schematic three-dimensional view of a viewing device according to the invention,

Fig. 2

1 is a schematic sectional view through the sighting device according to the invention from FIG. 1,

Figure 3

a schematic three-dimensional representation of the sighting device according to the invention from FIG. 1 obliquely from below,

Fig. 4

a schematic three-dimensional single view of a slot nozzle,

Fig. 5

a schematic sectional view through the slot nozzle of FIG. 4th

In the following figures, identical or similar elements or corresponding parts are provided with the same reference numerals, so that a corresponding renewed idea is dispensed with.

1 shows a schematic three-dimensional representation of a sighting device 20 according to the invention. Slit nozzles 1 arranged in parallel, which are also referred to as classifier nozzles 1, can be seen obliquely from above in a representation. It is also an air distribution box 2 can be seen, the compressed air from a central, not shown, air connection, on the classifier nozzles 1 divides. In addition, a trough 3 is provided, which is designed as a vibratory conveyor and has a bottom 19 which comprises four grooves 16. In addition, a material input 21 in the form of a kind of slide plate is shown schematically, on which also tobacco material 11 is shown, which is conveyed in the direction of the arrow into the trough 3 on the classifier nozzles 1. The tobacco material 11 is guided in the conveying direction 23 through the trough 3 to a material outlet 22 designed as a deflecting plate 4. As will be shown below, however, only the light parts 12 are discharged via the deflector 4.

The classifier nozzles 1 are spaced apart from each other. This can be better seen in Fig. 2, which shows a schematic sectional view of the device of Fig. 1, in the region of the classifier nozzles 1. The classifier nozzles 1 have a slot nozzle body 1 ', which is described in more detail with reference to FIG becomes. The trough 3 forms in connection with the slot nozzle bodies 1 'from a viewing space 18. From the nozzle slots 10 of the slot nozzle body 1 'emerges a nozzle flow 14 and an air flow, which impinges on the bottom 10. The nozzles produce a downward direction Air jet, which preferably perpendicular to the channel bottom meets, that is vertical in this embodiment exits. But it is also possible to arrange the classifier nozzles 1 so that the air flow hits the ground at an angle between 0 ° and 45 °, where 0 ° is perpendicular to the ground. Furthermore, it is also possible that the exiting air flow is a kind of air flow fan or air fan, which is fanned out at a corresponding angle. The angle is preferably less than and in particular preferably in the range of 20 ° or smaller. It is shown a wave-shaped bottom, so a bottom with four grooves 16, wherein the grooves may be circular or partially circular, partially elliptical or square. The advantage of the undulating bottom 19 is that heavy products or parts 13 are supplied to the lowest point of the soil. In this embodiment, the lowest point of the bottom in the channel 16 in each case lies opposite the nozzle slot 10, as a result of which the heavy part 13 is swirled up and freed of possibly adhering light parts 12. The light parts 12 are then entrained by the air flow or the air flow 15 and fed back through the slots or the spacings of the classifier nozzles 1 up the good product, ie the fluidized bed, which has formed in the upper portion 23 of the slot nozzle body 1 '. However, the channel bottom may also have any other configuration, whereby the effect described above is then not fully effective.

The width of the opening of the nozzle slots 10 may be in the range of about 5 mm. The length of the nozzle slots 10 in the range of 1 m to 2 m. The exit velocity of the air can be about 30 m / sec. be. The distance 25 of the slot nozzle body 1 'is selected so that the flow velocity of the air at the narrowest point between the nozzles about 5 m / sec. is. The distance at the narrowest point is about 30 mm.

The illustrated in Fig. 1, introduced into the area above the classifier nozzles 1 tobacco material 11 experiences through the air flow 15 a buoyancy upwards in the arrow direction. This buoyancy is sufficient to hold lightweight parts 12 in the upper region 23 of the classifier nozzles 1 in a fluidized bed. The light parts move there similar to a liquid, which is why the fluidized bed is also called fluid layer.

However, heavy parts 13 have a greater gravity than the buoyancy generated by the air flow 15 and move in the direction of the bottom 19 of the trough 3. There they are due to the vibrations of the trough 3 in the direction of the openings 5 promoted. The openings 5 are shown in Fig. 3, which shows a schematic three-dimensional representation of the embodiment of the invention of FIG. 1 in a representation from below right. Through the opening 5, the heavy parts can fall and are carried away. The lightweight parts reach the deflector 4, which is shown in dashed lines in Fig. 3. The openings 5 are arranged below the drainage plate 4. There are also other embodiments possible, for example, the trough 3 may end at this point. The light parts 12 are passed over the Ableitblech 4 over the openings. Between the deflector 4 and the trough 3, a gap is provided, through which the heavy parts 13, the openings 5 can be supplied. This gap is chosen so that the heavy parts 13 can proceed unhindered, but also can not leak too much false air.

The compressed air is generated by a fan 7 and fed to a suitable throttle body 8 via a connecting piece 6 to the air distributor 2. About the throttle body 8, the amount of air and Thus, the flow rate in the gaps or in the intervals 25 between the classifier nozzles 1 adjusted so that the desired visual effect is achieved. For uniform distribution of the compressed air in the air distribution box 2 and in the classifier nozzles 1 suitable Luftverteilbleche, which are not shown, or introduced other means for air distribution.

4 shows a schematic three-dimensional representation of a classifier nozzle 1 in a single view. The classifier nozzle 1 preferably comprises a suitable receiving device 9 at one or both ends. The receiving device 9 may be a clamping plate, a dovetail or a screw plate. With the receiving device, the classifier nozzle 1 can be attached to the air distribution box 2 such that the distances between the slot nozzles can be adjusted. The nozzle slot 10 preferably extends over the entire length of the classifier nozzle 1, but can also be designed only over part lengths as required.

It is an angle α recognizable, which is chosen so that on the one hand good transport of the tobacco is perpendicular to the cutting plane, but heavy parts 12 in the direction of the Slit between the nozzles 1 can slip. α is in the range of 6 ° to 90 °, preferably about 45 °. The illustrated angle β, that is the angle between the vertical wall and a wall arranged with the nozzle slot 10, is selected such that a sufficiently directed air jet can arise and lies in a range between 6 ° and 90 °, preferably at approximately 30 °.

The air emerging from the trough 3 is sucked off by means of a suitable suction hood, which is not shown. Otherwise can the device according to the invention be configured, as in the EP 0 361 815 B1 described device, in particular with reference to Figures 1, 2, 5 and 6 of this document.

An array of slot nozzles produces a plurality of downwardly directed air jets directed against a channel bottom. These air jets hit the gutter floor and are deflected upwards there. The air then flows through the gaps between the slot nozzles. The tobacco is abandoned above the slot nozzles. Heavy parts then fall against the prevailing air flow down to the gutter floor. The light product remains on the slot nozzles or in the upper region of the slot nozzles. In contrast to the prior art, the air flow direction is not directed upwards but initially downwards. As a result, used in the prior art thin perforated plates, which are arranged in the channel bottom and through which the air enters and can pollute and need to be cleaned at regular intervals, obsolete.

In a preferred embodiment, the trough 3 vibrates, shakes or vibrates with the bottom 19. The classifier nozzles 1 can then be stationary, that is, they can not resonate, shake or vibrate. Preferably, the classifier nozzles 1 are then not connected to the trough 3.

In an alternative embodiment, the trough 3 and the classifier nozzles 1 can be mechanically connected to one another and resonate, shake or vibrate. The trough 3 and the classifier nozzles 1 can also be inclined to the horizontal and can not move. In this type of embodiment, the sighted and exposed material is conveyed only by the classifier air and gravity.

LIST OF REFERENCE NUMBERS

1

Sichterdüse

1'

Die body

2

Air distribution box

3

trough

4

deflector

5

opening

6

spigot

7

fan

8th

throttle member

9

cradle

10

nozzle slot

11

tobacco material

12

easy part

13

difficult part

14

nozzle flow

15

airflow

16

gutter

18

view room

19

ground

20

Fluidized bed classifier

21

material input

22

material issue

23

upper area

24

conveying direction

25

distance

26

fluidized bed

Claims (15)

A viewing device (20) for separating heavy and light particles (12, 13) of tobacco material (11) in a viewing space (18), the viewing device (20) comprising at least one classifier nozzle (1) for generating a classifier stream (14, 15), characterized in that the classifier nozzle (1) comprises a body (1 ') which is arranged in the viewing space. Sighting device (20) according to claim 1, characterized in that the viewing device (20) is a fluidized-bed separator (20). Sighting device (20) according to claim 1 or 2, characterized in that an opening (10) of the classifier nozzle (1) to the bottom (19) of the viewing device (20) is arranged. Sighting device (20) according to claim 3, characterized in that that from the opening (10) of the Sichterdüse (1) kicking air stream (14) emerges substantially vertically downward. Sighting device (20) according to claim 3 or 4, characterized in that the bottom (19) of the viewing device (20) with at least one channel (16) is configured. A sighting device (20) according to any one of claims 1 to 5, characterized in that the classifier nozzle (1) is a slit nozzle extending at least partially from a material input (21) to a material dispenser (22). Sighting device (20) according to one of claims 1 to 6, characterized in that a material input (21) is provided which is arranged above or in the upper region (23) of the body (1 ') of the classifier nozzle (1). Sighting device (20) according to one of claims 1 to 7, characterized in that a material dispenser (22) is provided which is arranged in the upper region (23) of the body (1 ') of the classifier nozzle (1). Sighting device (20) according to one of claims 1 to 8, characterized in that the body (1 ') of the classifier nozzle (1) in cross-section transverse to a conveying direction (24) of the sighted tobacco material (11, 12) downwards and upwards is formed tapering. Sighting device (20) according to one of claims 1 to 9, characterized in that at least two classifier nozzles (1) are provided. Sighting device (20) according to claim 10, characterized in that the distance (25) of the classifier nozzles (1) to the bottom (19) is adjustable. A method of separating heavy and light particles (12, 13) of tobacco material (11) in a viewing space (18), wherein the viewing space (18) is bounded by a floor (19), tobacco material (11) entering the viewing space (18 ) and by means of a classifier stream (15), which is directed upward, light particles (12) in the upper region of the viewing space (18) are held, with heavy particles (13) in the region of the bottom (19) remain or get there, characterized in that the classifier stream (15) results from a reflection of an air stream (14) directed towards the bottom (19). A method according to claim 12, characterized in that the air flow (14) is designed such that a fluidized bed (26) light particles (12) in the upper region (23) of the viewing space (18) results. A method according to claim 12 or 13, characterized in that the tobacco material (11) is introduced into an upper area (23) in the viewing space (18). Method according to one of claims 12 to 14, characterized in that the bottom (19) is shaken or vibrated and / or is formed inclined.

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